The autonomous region of Extremadura in Spain is moving 40K desktops to Debian as did the French Gendarmerie (90K desktops) and the city of Munich (14K desktops).
See here for more info:
http://joinup.ec.europa.eu/news/extremadura-move-all-its-40000-desktops-open-sourceIn Europe there is definitively a strong trend to move out of Windows.
Thanks